US4951023A - Electromagnetic drive apparatus having a flat coil - Google Patents

Electromagnetic drive apparatus having a flat coil Download PDF

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Publication number
US4951023A
US4951023A US06/755,275 US75527585A US4951023A US 4951023 A US4951023 A US 4951023A US 75527585 A US75527585 A US 75527585A US 4951023 A US4951023 A US 4951023A
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US
United States
Prior art keywords
coil
drive apparatus
electrically conductive
electromagnetic drive
conductive element
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
US06/755,275
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English (en)
Inventor
Ludwig Erd
Klaus Menzel
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vacuumschmelze GmbH and Co KG
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Vacuumschmelze GmbH and Co KG
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Assigned to VACUUMSCHMELZE GMBH, A CORP OF GERMANY reassignment VACUUMSCHMELZE GMBH, A CORP OF GERMANY ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: MENZEL, KLAUS, ERD, LUDWIG
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Publication of US4951023A publication Critical patent/US4951023A/en
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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K33/00—Motors with reciprocating, oscillating or vibrating magnet, armature or coil system
    • H02K33/18—Motors with reciprocating, oscillating or vibrating magnet, armature or coil system with coil systems moving upon intermittent or reversed energisation thereof by interaction with a fixed field system, e.g. permanent magnets
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; ELECTRIC HEARING AIDS; PUBLIC ADDRESS SYSTEMS
    • H04R9/00—Transducers of moving-coil, moving-strip, or moving-wire type
    • H04R9/02—Details
    • H04R9/04—Construction, mounting, or centering of coil
    • H04R9/046—Construction
    • H04R9/047—Construction in which the windings of the moving coil lay in the same plane

Definitions

  • the present invention relates to electromagnetic drive devices, and in particular to electromagnetic drive devices employing a flat coil mounted for movement within a coil plane.
  • Electromagnetic drive devices such as for actuating printer needles and the like, are known having a flat coil disposed within an iron core, the iron core being magnetically coupled to at least one permanent magnet for generating a magnetic field in the coil plane which is substantially perpendicular with respect to the coil plane.
  • Such drive devices are particularly suited for limited, alternating linear movements or alternating movements about a segment of a circle, such as is required for driving printings devices.
  • the determining factor for initiating movement of the coil within the coil plane is the current within the coil situated in the magnetic field, the force acting on the flat coil is dependent upon a rapid response of the coil to voltage pulses. This applies for the current rise as well as the current decrease in the coil.
  • a plate or coating of electrically conductive material is disposed in the magnetic circuit for the apparatus parallel to and spaced from the coil plane. The dimensions of the plate or coating are selected so as to be coextensive with the area of movement of the flat coil within the coil plane. The coating or plate will thus cover the coil at every possible location thereof within the coil plane.
  • FIG. lA is a side elevational view of an electromagnetic drive apparatus constructed in accordance with the principles of the present invention in a first embodiment.
  • FIG. lB is a plan view of the electromagnetic drive apparatus shown in FIG. lA.
  • FIG. 2 is a plan view of a further embodiment of an electromagnetic drive apparatus constructed in accordance with the principles of the present invention for effecting limited circular movement.
  • FIG. 3 is a side elevational view of another embodiment for linear movement of an electromagnetic drive apparatus constructed in accordance with the principles of the present invention.
  • FIG. 4 is a side elevational view of a further embodiment of an electromagnetic drive apparatus for linear movement constructed in accordance with the principles of the present invention.
  • FIG. 5 is a side elevational view of yet another embodiment of an electromagnetic drive apparatus for linear movement constructed in accordance with the principles of the present invention.
  • FIGS. 1A and lB A first embodiment of an electromagnetic drive apparatus for effecting linear movement of the coil is shown in FIGS. 1A and lB.
  • the apparatus has a magnetic circuit including an iron core 1 and two permanent magnets 3. The minimum requirement is, however, that at least one permanent magnet be provided.
  • the iron core 1 serves as a return path for the magnetic field generated by the permanent magnets 3.
  • the permanent magnets 3 are disposed in proximity to a flat coil 2.
  • the flat coil 2 has dimensions in the direction of the coil axis which are relatively small in comparison to the distance between the sections of a winding of the coil which lie opposite each other.
  • the windings are wound to form a rectangle, as shown in FIG. lB, so that the current within the flat coil generates a force acting substantially in one direction over a large portion of the current path.
  • the flat coil 2 is mounted for longitudinal linear movement within the core 1 by any suitable means well known to those skilled in the art and therefore not shown in the drawings.
  • the coil 2 moves in the direction of the double arrow shown in FIGS. lA and lB.
  • the magnetic field is substantially perpendicular in the plane of the drawing to the arrow as shown in FIG. lA.
  • the coil 2 will thus be displaced to the right and left of the drawings.
  • the magnetic forces acting on the coil conductor causes movement in these directions when the coil is supplied with a current.
  • the coil 2 is shown in an intermediate position in solid lines, and at the extreme left and right positions indicated by dashed lines.
  • the iron core 1 has a plate or coating 4 consisting of electrically conductive material disposed thereon at a side thereof opposite the permanent magnets 3.
  • the plate or coating 4 may consist, for example, of copper.
  • the plate or coating 4 has an area which is coextensive with the entire area or range of possible movement of the coil 2 within the coil plane, and is spaced from and parallel to the coil plane containing the coil 2.
  • the least complicated shape for the plate or coating 4 is substantially a rectangle.
  • An eddy current forms within the plate or coating 4 given a change of current direction in the flat coil 2. This eddy current proceeds substantially parallel to the coil conductors of the coil 2, thus promoting fast rise or fast decrease, as the case may be, of the current within the flat coil 2 without excessively large magnetic field changes occurring in the magnetic circuit formed by the iron core 1 and the permanent magnets 3.
  • the plate or coating 4 is magnetically coupled within the magnetic circuit.
  • FIG. 2 A further embodiment of an electromagnetic drive apparatus constructed in accordance with the principles of the present invention for limited circular movement is shown in plan view in FIG. 2.
  • This embodiment has a core lA which is a segment of a ring, and also employs similar shaped permanent magnets 3a, also formed as segments of a ring concentric with the ring segment defined by the core 1a.
  • the flat coil 2a in this embodiment is in the form of a trapezoid having two substantially straight sides joining two opposite sides which are slightly curved, again essentially forming a segment of a ring, as indicated by the convergence of the sides at an imaginary point 5.
  • FIG. 2 further includes a plate or coating 4a, which is also formed as a segment of a ring and, as in the previously-discussed embodiment, is coextensive with the entire range of movement of the flat coil 2a.
  • the curved plate or coating 4a is again parallel to and spaced from the plane containing the coil 2 a. Limited movement along an arc of a circle, as indicated by the curved double arrow, is achieved by the coil 2a in the embodiment of FIG. 2.
  • a single permanent magnet may be utilized instead of two permanent magnets.
  • FIG. 3 employing two parallel plates or coatings 4.
  • One plate is disposed adjacent the permanent magnets 3 on one side of the flat coil 2, and the other plate or coating 4 is disposed spaced from the coil 2 on the opposite side thereof.
  • the use of two such plates or coatings 4 even further promotes rapid rise and decay times of the current in the coil 2.
  • This embodiment can also be utilized in the circular arrangement of FIG. 2.
  • FIG. 4 Another embodiment of the drive apparatus is shown in FIG. 4 employing two pairs of permanent magnets 3, each pair of magnets 3 being covered by a plate or coating 4 disposed on opposite sides of the flat coil 2.
  • FIG. 5 A modification of this arrangement is shown in FIG. 5, again employing two pairs of permanent magnets 3, but only one plate or coating 4.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Power Engineering (AREA)
  • Linear Motors (AREA)
  • Reciprocating, Oscillating Or Vibrating Motors (AREA)
  • Electromagnets (AREA)
US06/755,275 1984-07-14 1985-07-15 Electromagnetic drive apparatus having a flat coil Expired - Fee Related US4951023A (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3426042 1984-07-14
DE19843426042 DE3426042A1 (de) 1984-07-14 1984-07-14 Elektrischer flachspulenantrieb

Publications (1)

Publication Number Publication Date
US4951023A true US4951023A (en) 1990-08-21

Family

ID=6240681

Family Applications (1)

Application Number Title Priority Date Filing Date
US06/755,275 Expired - Fee Related US4951023A (en) 1984-07-14 1985-07-15 Electromagnetic drive apparatus having a flat coil

Country Status (5)

Country Link
US (1) US4951023A (de)
EP (1) EP0170056B1 (de)
JP (1) JPS6140009A (de)
AT (1) ATE36784T1 (de)
DE (2) DE3426042A1 (de)

Cited By (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5122703A (en) * 1989-06-21 1992-06-16 501 Hitachi Metals, Ltd. Integrally molded armature for swing-type actuator
US5148071A (en) * 1990-03-22 1992-09-15 Hitachi Metals, Ltd. Swing-type actuator with thin reinforced movable coil
US5165090A (en) * 1990-05-24 1992-11-17 Hitachi Metals, Ltd. Swing-type actuator
US5168184A (en) * 1990-10-04 1992-12-01 Hitachi Metals, Ltd. Swing-type actuator
US5168185A (en) * 1990-10-09 1992-12-01 Hitachi Metals, Ltd. Swing-type actuator
US5200727A (en) * 1990-10-11 1993-04-06 Tokimec Inc. Force generating apparatus
US5459359A (en) * 1992-04-30 1995-10-17 Hitachi Metals, Ltd. Swing-type actuator
US5576583A (en) * 1992-04-30 1996-11-19 Hitachi Metals, Ltd. Swing-type actuator
US5581422A (en) * 1993-02-09 1996-12-03 Hitachi Metals, Ltd. Actuator with moveable coil and recording apparatus
US5984210A (en) * 1997-11-04 1999-11-16 Caterpillar Inc. Fuel injector utilizing a solenoid having complementarily-shaped dual armatures
GB2353362A (en) * 1999-08-19 2001-02-21 Bayerische Motoren Werke Ag Coil Transducer With Magnetic Field Compensating Means
US6781259B2 (en) * 2000-08-04 2004-08-24 Koninklijke Philips Electronics N.V. Electrical appartus having an actuator
US6830173B2 (en) 2000-08-25 2004-12-14 Senco Products, Inc. Impact device
US20070024277A1 (en) * 2005-07-29 2007-02-01 Automotive Systems Laboratory, Inc. Magnetic crash sensor
US20080068008A1 (en) * 2003-09-19 2008-03-20 Watson William T Magnetic crash sensor
US20080109177A1 (en) * 2003-09-19 2008-05-08 Cech Leonard S Magnetic crash sensor
US20080211646A1 (en) * 2003-09-19 2008-09-04 Cech Leonard S Magnetic crash sensor
US20090167300A1 (en) * 2003-09-19 2009-07-02 Cech Leonard S Magnetic crash sensor
US20090212889A1 (en) * 2005-05-20 2009-08-27 Elliot Brooks Eddy current inductive drive electromechanical linear actuator and switching arrangement
US20090319212A1 (en) * 1999-08-26 2009-12-24 Tk Holdings, Inc. Magnetic crash sensor
US20100206990A1 (en) * 2009-02-13 2010-08-19 The Trustees Of Dartmouth College System And Method For Icemaker And Aircraft Wing With Combined Electromechanical And Electrothermal Pulse Deicing
US11218811B2 (en) * 2017-03-07 2022-01-04 Harman International Industries, Incorporated Loudspeaker
US11450302B2 (en) 2018-03-07 2022-09-20 Harman International Industries, Incorporated Loudspeaker with magnets in ferrofluid
US20250079101A1 (en) * 2023-08-31 2025-03-06 Siemens Industry, Inc. Magnetic switch for hybrid circuit breaker applications

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE8711811U1 (de) * 1987-09-01 1987-10-15 Schmall, Karl-Heinz, 7570 Baden-Baden Feinantrieb für ein Laserwerkzeug
DE3901129A1 (de) * 1989-01-17 1990-07-19 Bso Steuerungstechnik Gmbh Linearantrieb
DE10354777B4 (de) * 2003-11-21 2008-03-27 Sult Gmbh Sortiereinrichtung zum Sortieren von unterschiedlichen Stoffen
CN113972808B (zh) * 2021-10-27 2023-05-09 歌尔股份有限公司 一种线性振动马达

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1254923A (fr) * 1959-08-28 1961-03-03 Durowe A G Dispositif de commande électrique pour l'entraînement d'un organe oscillant mécanique
GB899678A (en) * 1958-07-02 1962-06-27 Nat Res Dev Improvements in or relating to reciprocating electric generators or motors
US3136934A (en) * 1960-03-31 1964-06-09 Printed Motors Inc Reciprocating linear motor system
US3161793A (en) * 1960-09-13 1964-12-15 Nat Res Dev Electrical machines involving the reciprocation of moving parts
GB989169A (en) * 1960-09-13 1965-04-14 Nat Res Dev Improvements in or relating to electrical machines
US3935399A (en) * 1972-12-27 1976-01-27 Ragnar Lian Loud speakers
US4022311A (en) * 1975-11-19 1977-05-10 Ncr Corporation Electrodynamic actuator
DE2654075A1 (de) * 1976-11-29 1978-06-01 Papst Motoren Kg Linearmotor
US4129390A (en) * 1976-05-19 1978-12-12 General Electric Company Stacked blade matrix printer heads
US4211493A (en) * 1978-08-30 1980-07-08 Burroughs Corporation Impact printing apparatus
US4260269A (en) * 1979-06-25 1981-04-07 General Electric Company Split stackable printing blades for matrix printer head
US4349283A (en) * 1980-09-05 1982-09-14 General Instrument Corporation Hammer for dot matrix printer

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB899678A (en) * 1958-07-02 1962-06-27 Nat Res Dev Improvements in or relating to reciprocating electric generators or motors
FR1254923A (fr) * 1959-08-28 1961-03-03 Durowe A G Dispositif de commande électrique pour l'entraînement d'un organe oscillant mécanique
US3136934A (en) * 1960-03-31 1964-06-09 Printed Motors Inc Reciprocating linear motor system
US3161793A (en) * 1960-09-13 1964-12-15 Nat Res Dev Electrical machines involving the reciprocation of moving parts
GB989169A (en) * 1960-09-13 1965-04-14 Nat Res Dev Improvements in or relating to electrical machines
US3935399A (en) * 1972-12-27 1976-01-27 Ragnar Lian Loud speakers
US4022311A (en) * 1975-11-19 1977-05-10 Ncr Corporation Electrodynamic actuator
US4129390A (en) * 1976-05-19 1978-12-12 General Electric Company Stacked blade matrix printer heads
DE2654075A1 (de) * 1976-11-29 1978-06-01 Papst Motoren Kg Linearmotor
US4211493A (en) * 1978-08-30 1980-07-08 Burroughs Corporation Impact printing apparatus
US4260269A (en) * 1979-06-25 1981-04-07 General Electric Company Split stackable printing blades for matrix printer head
US4349283A (en) * 1980-09-05 1982-09-14 General Instrument Corporation Hammer for dot matrix printer

Cited By (35)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5122703A (en) * 1989-06-21 1992-06-16 501 Hitachi Metals, Ltd. Integrally molded armature for swing-type actuator
US5148071A (en) * 1990-03-22 1992-09-15 Hitachi Metals, Ltd. Swing-type actuator with thin reinforced movable coil
US5165090A (en) * 1990-05-24 1992-11-17 Hitachi Metals, Ltd. Swing-type actuator
US5168184A (en) * 1990-10-04 1992-12-01 Hitachi Metals, Ltd. Swing-type actuator
US5168185A (en) * 1990-10-09 1992-12-01 Hitachi Metals, Ltd. Swing-type actuator
US5200727A (en) * 1990-10-11 1993-04-06 Tokimec Inc. Force generating apparatus
GB2248690B (en) * 1990-10-11 1994-09-07 Tokimec Inc A pickup torquer
US5576583A (en) * 1992-04-30 1996-11-19 Hitachi Metals, Ltd. Swing-type actuator
US5459359A (en) * 1992-04-30 1995-10-17 Hitachi Metals, Ltd. Swing-type actuator
US5581422A (en) * 1993-02-09 1996-12-03 Hitachi Metals, Ltd. Actuator with moveable coil and recording apparatus
US5984210A (en) * 1997-11-04 1999-11-16 Caterpillar Inc. Fuel injector utilizing a solenoid having complementarily-shaped dual armatures
GB2353362A (en) * 1999-08-19 2001-02-21 Bayerische Motoren Werke Ag Coil Transducer With Magnetic Field Compensating Means
GB2353362B (en) * 1999-08-19 2003-10-08 Bayerische Motoren Werke Ag A transducer
US20090319212A1 (en) * 1999-08-26 2009-12-24 Tk Holdings, Inc. Magnetic crash sensor
US8180585B2 (en) 1999-08-26 2012-05-15 Tk Holdings, Inc. Magnetic crash sensor
US6781259B2 (en) * 2000-08-04 2004-08-24 Koninklijke Philips Electronics N.V. Electrical appartus having an actuator
US6830173B2 (en) 2000-08-25 2004-12-14 Senco Products, Inc. Impact device
US20080068008A1 (en) * 2003-09-19 2008-03-20 Watson William T Magnetic crash sensor
US7839143B2 (en) 2003-09-19 2010-11-23 Tk Holdings Inc. Eddy current magnetic crash sensor
US20080211646A1 (en) * 2003-09-19 2008-09-04 Cech Leonard S Magnetic crash sensor
US20090167300A1 (en) * 2003-09-19 2009-07-02 Cech Leonard S Magnetic crash sensor
US7839142B2 (en) 2003-09-19 2010-11-23 Tk Holdings, Inc. Magnetic crash sensor
US20080109177A1 (en) * 2003-09-19 2008-05-08 Cech Leonard S Magnetic crash sensor
US7772839B2 (en) 2003-09-19 2010-08-10 Tk Holdings, Inc. Eddy current magnetic crash sensor
US7777600B2 (en) 2004-05-20 2010-08-17 Powerpath Technologies Llc Eddy current inductive drive electromechanical liner actuator and switching arrangement
US20110068884A1 (en) * 2004-05-20 2011-03-24 Powerpath Technologies Llc Electromechanical actuator
US8134438B2 (en) 2004-05-20 2012-03-13 Powerpath Technologies Llc Electromechanical actuator
US20090212889A1 (en) * 2005-05-20 2009-08-27 Elliot Brooks Eddy current inductive drive electromechanical linear actuator and switching arrangement
US8134437B2 (en) 2005-05-20 2012-03-13 Powerpath Technologies Llc Eddy current inductive drive electromechanical linear actuator and switching arrangement
US7388370B2 (en) 2005-07-29 2008-06-17 Automotive Systems Laboratory Systems, Inc. Magnetic crash sensor
US20070024277A1 (en) * 2005-07-29 2007-02-01 Automotive Systems Laboratory, Inc. Magnetic crash sensor
US20100206990A1 (en) * 2009-02-13 2010-08-19 The Trustees Of Dartmouth College System And Method For Icemaker And Aircraft Wing With Combined Electromechanical And Electrothermal Pulse Deicing
US11218811B2 (en) * 2017-03-07 2022-01-04 Harman International Industries, Incorporated Loudspeaker
US11450302B2 (en) 2018-03-07 2022-09-20 Harman International Industries, Incorporated Loudspeaker with magnets in ferrofluid
US20250079101A1 (en) * 2023-08-31 2025-03-06 Siemens Industry, Inc. Magnetic switch for hybrid circuit breaker applications

Also Published As

Publication number Publication date
DE3426042A1 (de) 1986-01-16
JPS6140009A (ja) 1986-02-26
DE3564645D1 (en) 1988-09-29
ATE36784T1 (de) 1988-09-15
EP0170056A1 (de) 1986-02-05
EP0170056B1 (de) 1988-08-24

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